Search

Introduction FEIBA® consists of zymogens and traces of activated forms of procoagulant factors II, VII, IX, X, anticoagulants protein C and TFPI, and small amounts of cofactors FV, FVIII and protein S, in a balanced ratio. As shown previously, FII- FXa complex plays a key role in FEIBA's mode of action (MoA). Methods Thrombin generation ( TG) was measured by spiking coagulation factors, cofactors and inhibitors to high titer FVIII inhibitor plasma, and in plasma samples from patients in a phase 3 clinical study evaluating the safety and efficacy of FEIBA prophylaxis in haemophilia A patients with inhibitors. Results Increasing the FXa/ FII ratio improved TG, while adding coagulation enzyme components had a negligible effect. Adding FX, FIX, and FVII increased the peak thrombin and decreased the lag time. The presence of FV and phospholipids led to faster TG, while protein C and protein S reduced the amount of peak thrombin. TFPI appeared to have no effect. Patients on prophylaxis with FEIBA® showed higher peak thrombin and AUC with elevated FII, FX, FIX, FVIIa, and protein C levels, and experienced significantly less bleeding episodes than those receiving on-demand treatment. Conclusion These experiments showed that although the FII- FXa complex induced immediate thrombin formation on the activated platelet surface, other procoagulant components of FEIBA were necessary to achieve an optimal thrombin burst. The presence of the pro- and anti-coagulants in FEIBA provides a haemostatic balance, and is thus expected to prevent thrombotic events. Recent clinical data verified the postulated MoA of FEIBA in prophylaxis treatment. [ABSTRACT FROM AUTHOR]

Abstract: Rurioctocog alfa pegol is an extended-half-life full-length recombinant factor VIII (FVIII) bound to 20-kDa polyethylene glycol (PEG) that has been shown to be well tolerated and efficacious in the treatment and prevention of bleeding events in previously treated patients with severe hemophilia A. Here, we present a comprehensive analysis of immunogenicity data collected during 6 clinical studies of rurioctocog alfa pegol, including a total of 360 unique previously treated patients with severe hemophilia A. The analysis included treatment-emerging FVIII-neutralizing antibodies (FVIII inhibitors); preexisting and treatment-emerging antibodies binding to FVIII, PEG-FVIII, or PEG; and treatment-emerging antibodies binding to Chinese hamster ovary host cell proteins. Moreover, the potential association between the presence of these binding antibodies and adverse events (AEs) observed in patients was investigated, and the potential impact of these antibodies on the incremental recovery of rurioctocog alfa pegol in patients was analyzed. Overall, the data indicate that rurioctocog alfa pegol is not associated with any unexpected immunogenicity characteristics. Of 360 patients, 1 patient developed a transient FVIII inhibitor with a titer of 0.6 Bethesda units per mL, which was not associated with any serious AEs. Antibodies binding to FVIII, PEG-FVIII, or PEG were not detected at the time when the inhibitor was present. Moreover, 54 of 360 patients either entered the clinical studies with preexisting binding antibodies or developed these antibodies after exposure to rurioctocog alfa pegol. These antibodies were transient in most patients and did not show any causal relationship to either AEs or spontaneous bleeding episodes., (© 2024 by The American Society of Hematology. Licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0), permitting only noncommercial, nonderivative use with attribution. All other rights reserved.)

Background: Patients with hemophilia who have recurrent hemarthroses develop hemophilic arthropathy (HA). Regular prophylaxis with factor (F) VIII (FVIII) can reduce HA, but there is a need for objective outcome measures to evaluate treatment efficacy., Objectives: Evaluate and assess collagen turnover biomarkers in patients with hemophilia A to determine the efficacy of rurioctocog alfa pegol treatment and understand their potential as tools for guiding treatment decisions and monitoring outcomes., Methods: Joint remodeling was assessed by analyzing serum levels of collagen remodeling products at baseline and months 3, 6, 9, and 12 in a 98 patient subset receiving pharmacokinetics-guided prophylaxis with rurioctocog alfa pegol, targeting FVIII trough levels of 1 to 3 International Units (IU)/dL or 8 to 12 IU/dL (PROPEL study, NCT0285960)., Results: Basement membrane metabolism-related type 4 collagen remodeling products (C4M and PRO-C4) decreased after 3 months at all time points by up to 25% at 1 to 3 IU/dL (P = .049, P < .0001) and 8 to 12 IU/dL FVIII trough levels (P = .0002, P < .0001). Interstitial tissue metabolism-related type 3 (C3M) and 5 (PRO-C5) collagen remodeling products decreased after 3 months, by up to 19% at 1 to 3 IU/dL FVIII trough level (P = .0001, P = .009) and 23% at 8 to 12 IU/dL FVIII trough level (P = .0002, P = .001). An increase of up to 12% was seen for cartilage metabolism-related type 2 collagen product (PRO-C2, not C2M) after 6 months at both trough levels (P = .01, P = .005). When stratified by prior treatment, changes in C3M (P = .03) and C4M (P = .02) levels were observed between trough levels for prior on-demand treatment but not for prophylaxis prior to study entry., Conclusion: Joint improvement measured by collagen remodeling biomarkers specific to the basement membrane, interstitial matrix, and cartilage was seen with pharmacokinetics-guided prophylaxis. These collagen remodeling biomarkers warrant further exploration as biomarkers to guide treatment toward improvement in HA., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: The phase 3, prospective PROPEL study demonstrated that pharmacokinetic (PK)-guided prophylaxis targeting elevated factor VIII (FVIII) troughs in patients with hemophilia A resulted in lower annualized bleeding rates (ABRs) and a higher proportion of patients experiencing zero bleeds in the second 6 months of treatment when targeting a FVIII trough of 8-12% versus 1-3%., Objective: To investigate the benefit of PK-guided prophylaxis with rurioctocog alfa pegol targeting two FVIII trough levels in specific patient subgroups in a post hoc analysis using data from PROPEL., Design: This is a post hoc analysis of data from the PROPEL study. The design and primary outcomes of the prospective, randomized PROPEL study (NCT02585960) have been reported previously., Methods: This post hoc analysis reports data stratified by FVIII half-life ( t 1/2 ), hemophilic arthropathy status, number of target joints at screening, previous treatment regimen, and ABR range in the 12 months before study entry., Results: Targeting an elevated FVIII trough of 8-12% was associated with higher average FVIII levels over time, regardless of FVIII t 1/2 at baseline. The decrease in total ABR between the 8-12% and 1-3% arms was greatest in patients with a FVIII t 1/2 of 6 to <12 h (0.7 versus 3.5); a higher number of target joints, that is, at least four target joints, at baseline (0.2 versus 1.6); the presence of arthropathy (0.1 versus 1.7); and those previously treated on-demand (0.3 versus 1.8)., Conclusion: These results support the feasibility of targeting elevated FVIII levels using personalized rurioctocog alfa pegol prophylaxis. These benefits may be especially important in patients with a short FVIII t 1/2 and those receiving standard prophylaxis with frequent breakthrough bleeds, arthropathy, and target joints., Registration: ClinicalTrials.gov Identifier: NCT02585960; https://clinicaltrials.gov/ct2/show/NCT02585960., Competing Interests: The authors declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: C.E.-E. has received grant/research support from Biotest, CSL Behring, Octapharma, Shire (a Takeda company), and Sobi; honoraria for lectures/advisory boards from Bayer, Biotest, CSL Behring, Grifols, Kedrion, Novo Nordisk, Octapharma, Pfizer, Roche/Chugai, Shire (a Takeda company), and Sobi; and consultancy fees from BioMarin, Biotest, CSL Behring, Grifols, Novo Nordisk, Octapharma, Roche/Chugai, Shire (a Takeda company), and Sobi. R.K. has received grant/research support from Bayer, BioMarin, CSL Behring, Novo Nordisk, Octapharma, Pfizer, and Shire (a Takeda company); consultancy fees from Bayer, BioMarin, Biotest, CSL Behring, Grifols, Novo Nordisk, Octapharma, Pfizer, Roche, Shire (a Takeda company), and Sobi; and speaker bureau fees from Bayer, BioMarin, Biotest, CSL Behring, Grifols, Novo Nordisk, Octapharma, Pfizer, Roche, Shire (a Takeda company), and Sobi. M.E. has received grant/research support from Genentech, Novo Nordisk, Sanofi, Takeda, and uniQure; and consultancy fees from Bayer, BioMarin, CSL Behring, FDA, Genentech/Roche, Kedrion, Novo Nordisk, Pfizer, Sanofi, and Shire (a Takeda company). O.S. is an employee of the Institute of Blood Pathology and Transfusion Medicine of the National Academy of Medical Sciences of Ukraine; and has received grant/research support from CSL Behring, Novo Nordisk, Sanofi, Shire (a Takeda company), and Pfizer; and speaker bureau fees from LFB, Novo Nordisk, Octapharma, Pfizer, Roche, and Shire (a Takeda company). S.T. is an employee of Takeda Development Center Americas, Inc. and a Takeda stock owner. At the time of the study, W.E. was an employee of Baxalta Innovations GmbH, a Takeda company and was a Takeda stock owner. At the time of the study, I.H. was an employee of Baxalta GmbH, a Takeda company, and was a Takeda stock owner. H.-Y.L is an employee of Baxalta GmbH, a Takeda company, and is a Takeda stock owner. P.C. is on the advisory boards of Bayer, Boehringer Ingelheim, Chugai, CSL Behring, Freeline, Novo Nordisk, Pfizer, Roche, Sanofi, Sobi, Spark, and Takeda; and has received grant/research support from Bayer, CSL Behring, Freeline, Novo Nordisk, Pfizer, Sobi, and Takeda. J.W. has received grant/research support and honoraria for lectures from Alexion, Alnylam, Baxalta/Shire (a Takeda company), Bayer, CSL Behring, Ferring, Novo Nordisk, Octapharma, Rigel, Roche, Sanofi, Siemens, Sobi, and Werfen., (© The Author(s), 2023.)

Aim: To determine the immunogenicity, safety, and efficacy of rurioctocog alfa pegol in previously untreated patients (PUPs) with severe hemophilia A (HA)., Methods: This prospective, phase 3 study (NCT02615691) was conducted in PUPs, or patients with ≤2 exposure days (EDs) prior to screening, aged <6 years with severe HA. The primary endpoint was incidence of factor VIII (FVIII) inhibitor development. This protocol-specified interim analysis was conducted after 50 patients had completed ≥50 EDs without developing FVIII inhibitors or had developed a confirmed inhibitor at any time., Results: Of the enrolled patients, 59/80 (73.8%) received ≥1 dose of rurioctocog alfa pegol; 54 received prophylaxis, and 35 on-demand treatment. Incidence of inhibitor development was 0.19 (10/52). Total annualized bleeding rate (95% CIs) was 3.2 (2.0-5.0) for patients receiving prophylaxis and 3.2 (1.6-6.3) for on-demand treatment. Hemostatic efficacy of most bleedings was rated as 'excellent' or 'good' after 24 hours (122/131 [93.1%]) and at resolution (161/170 [94.7%]). Five patients received ≥1 dose of rurioctocog alfa pegol for immune tolerance induction (ITI) and 1 patient was defined as having ITI success. Thirteen patients experienced 14 treatment-related adverse events, including 10 cases of FVIII inhibitor development., Conclusion: This is the first prospective study of rurioctocog alfa pegol for the treatment of PUPs with severe HA., Trial Registration: This trial is registered at ClinicalTrials.gov (CT.gov identifier: NCT02615691).

Introduction: In patients with haemophilia A undergoing surgery, factor VIII (FVIII) replacement therapy by continuous infusion (CI) may offer an alternative to bolus infusion (BI)., Aim: To compare the perioperative haemostatic efficacy and safety of antihaemophilic factor (recombinant) (ADVATE ® ; Baxalta US Inc., a Takeda company, Lexington, MA, USA) CI or BI administration., Methods: In this multicentre, phase III/IV, controlled study (NCT00357656), 60 previously treated adult patients with severe or moderately severe disease undergoing elective unilateral major orthopaedic surgery (knee replacement, n = 48; hip surgery, n = 4; other, n = 8) requiring drain placement were randomized to receive antihaemophilic factor (recombinant) CI (n = 29) or BI (n = 31) through postoperative day 7. Primary outcome measure was cumulative packed red blood cell (PRBC)/blood volume in the drainage fluid within 24 h after surgery, used to establish non-inferiority of CI to BI., Results: CI:BI ratio of cumulative PRBC volume in the 24-h drainage fluid was 0.92 (p-value <.001 for non-inferiority; 95% confidence interval, 0.82-1.05). Total antihaemophilic factor (recombinant) dose per kg body weight received in the combined trans- and postoperative periods was similar with CI and BI to maintain targeted FVIII levels during/after surgery. Treatment-related adverse events (AEs) were reported in five patients treated by CI (eight events) and five treated by BI (six events), including two serious AEs in each arm., Conclusion: CI administration of antihaemophilic factor (recombinant) is a viable alternative to BI in patients with haemophilia A undergoing major orthopaedic surgery, providing comparable efficacy and safety., (© 2021 Takeda Pharmaceuticals International AG, Zurich Switzerland. Haemophilia published by John Wiley & Sons Ltd.)

Introduction: Previous studies reported the efficacy and safety profile of extended half-life PEGylated recombinant factor VIII (FVIII) rurioctocog alfa pegol (TAK-660, SHP660, BAX 855) in preventing bleeding in haemophilia A patients., Aim: This study evaluated long-term safety and efficacy of rurioctocog alfa pegol for prophylaxis and treatment of bleeding in previously treated children and adults., Methods: In this phase 3b, prospective, open-label, multicentre study (NCT01945593), eligible patients ≤ 75 years with severe haemophilia A (FVIII < 1%) received prophylactic rurioctocog alfa pegol in a fixed dose (FD, twice-weekly or less frequent) or pharmacokinetic (PK)-tailored dose regimen. Co-primary endpoints were incidence of confirmed FVIII inhibitory antibody development and spontaneous annualized bleed rate (ABR), analysed using a generalised linear model. Secondary endpoints included overall haemostatic efficacy, occurrence of adverse events and health-related quality of life (HRQoL)., Results: Overall, 216 patients were included; mean (SD) age at enrolment was 22.8 (15.7) years. No patients developed confirmed FVIII inhibitors. The point estimate (95% CI) of mean spontaneous ABR was 1.20 (0.92-1.56) among 186 patients receiving twice-weekly FD prophylaxis and 0.96 (0.54-1.71) among 25 patients receiving PK-tailored prophylaxis. Overall haemostatic efficacy was rated good or excellent in 88.6% of all bleeds. No new safety signals were observed. Patients reported improvements in HRQoL measures of pain, and physical and mental well-being., Conclusion: These results highlight the long-term safety and efficacy of rurioctocog alfa pegol prophylaxis in previously treated children and adults with severe haemophilia A, with a safety profile similar to previous studies and continuing ABR reduction., (© 2020 The Authors. Haemophilia published by John Wiley & Sons Ltd.)

Introduction: Antihaemophilic factor (recombinant) (rAHF; ADVATE ® ) is approved for prophylaxis and treatment of bleeding in children and adults with haemophilia A. Reconstitution in 2 mL sterile water for injection instead of 5 mL allows for a 60% reduction in infusion volume and administration time, but could increase the likelihood of hypersensitivity and infusion-related reactions, especially in children., Aim: To assess local tolerability, safety and effectiveness of rAHF 2 mL during routine clinical practice factor VIII (FVIII) replacement (on-demand and prophylaxis) in children with severe (FVIII < 1%) or moderately severe (FVIII 1%-2%) haemophilia A., Methods: This was a prospective, non-interventional, postauthorization safety surveillance study (NCT02093741). Eligible patients were previously treated with rAHF and had a negative inhibitor test result during ≤10 exposure days prior to study entry., Results: Of 65 patients enrolled (0-11 years of age), 54 and 11 had severe and moderately severe haemophilia A, respectively; 56 patients received prophylaxis, and 11 had ≤50 exposure days, of which 4 had ≤4 exposure days. No patients reported local hypersensitivity reactions, treatment-related adverse events or developed inhibitors. Investigators rated overall effectiveness of rAHF 2 mL prophylaxis as excellent or good. Ninety-four bleeding events in 34 patients were treated. Haemostatic effectiveness was rated as excellent or good for 75.8% of bleeds; 86.2% of bleeds required 1 or 2 infusions., Conclusion: In children with severe/moderately severe haemophilia A, no hypersensitivity reactions were reported with rAHF 2 mL treatment, and the safety and effectiveness are consistent with data previously reported for rAHF 5 mL., (© 2020 The Authors. Haemophilia published by John Wiley & Sons Ltd.)

Hemostatic management is essential for ensuring the safety of patients with hemophilia during surgery. This phase 3, prospective, uncontrolled trial, evaluated hemostatic efficacy, consumption, and safety of a recombinant factor IX concentrate, nonacog gamma (BAX 326, Rixubis ® [Baxalta US Inc., a Takeda company, Lexington, MA, USA]), in intraoperative and postoperative settings in previously treated patients (PTPs) with severe or moderately severe hemophilia B undergoing elective surgery (N = 38 surgeries; 21 major, 17 minor). Predefined preoperative hemostatic factor IX levels (80-100% of normal for major and 30-60% for minor surgeries) were maintained for each patient. Intraoperative efficacy was rated as "excellent" or "good" for all surgeries. Postoperative hemostatic efficacy on day of discharge was rated as "excellent," "good," and "fair," respectively, for 29 (76.3%), 7 (18.4%), and 2 (5.3%) surgical procedures. All adverse events were considered unrelated to study drug; most frequently reported was mild procedural pain (9 patients). No thrombotic events, severe allergic reactions, or inhibitor formation were observed. Nonacog gamma was well tolerated and effective for intraoperative and postoperative hemostatic management of PTPs with hemophilia B.NCT01507896, EudraCT: 2011-000413-39.

This phase 3, prospective, open-label, multicenter, continuation study (NCT01286779) investigated the use of a recombinant factor IX (FIX), nonacog gamma (BAX 326, RIXUBIS ® ) in patients with severe or moderately severe hemophilia B. The study population included 85 patients transitioning from a phase 1/3 pivotal study (NCT01174446), a pediatric study (NCT01488994), and 30 newly recruited patients, naïve to nonacog gamma. Patients received nonacog gamma as prophylaxis treatment (standard, modified or PK-tailored) or on-demand, as determined by the investigator. Treatment was assessed for safety, immunogenicity, hemostatic efficacy and consumption. In this study, after ≥100 exposure days, nonacog gamma resulted in no treatment-related serious adverse events, and no patients developed inhibitory antibodies to FIX. Nonacog gamma was efficacious at controlling bleeding episodes, with an 89.1% overall hemostatic efficacy rating of excellent or good, and 56% of bleeds resolved with one infusion. The annualized bleeding rate was considerably lower during prophylactic treatment (median ABR of 1.3 in 108 patients) than during on-demand treatment (median ABR of 16.5 in 13 patients). These results show that in previously treated patients and nonacog gamma-naïve patients, long-term use of nonacog gamma had acceptable safety and tolerability, and was efficacious as a prophylactic treatment for the management of bleeding episodes.NCT01286779, EudraCT: 2010-022726-33.

Introduction: Rurioctocog alfa pegol (BAX 855, TAK-660) is a PEGylated, full-length, recombinant factor VIII (rFVIII) with extended half-life developed from unmodified rFVIII (antihaemophilic factor [recombinant])., Aim: To determine the perioperative haemostatic efficacy and safety of rurioctocog alfa pegol in male previously treated patients (PTPs) with severe haemophilia A., Methods: This multicentre, single-arm, phase III study included PTPs who were to undergo major or minor elective or minor emergency surgical, dental or other invasive procedures. Rurioctocog alfa pegol dose and frequency were individualized based on patients' pharmacokinetic profiles for major surgeries and by rurioctocog alfa pegol incremental recovery for minor surgeries. Haemostatic efficacy was assessed using the Global Haemostatic Efficacy Assessment score., Results: Twenty-one patients aged 16-61 years underwent 21 major and five minor surgeries. For all 24 evaluable surgeries, overall haemostatic efficacy was rated as excellent and blood loss comparable to that expected in non-haemophilic patients. No blood transfusions were required intraoperatively but were administered postoperatively for four surgeries in three patients. Five injury-related postoperative bleeding episodes occurred in five patients, of which two required additional rurioctocog alfa pegol treatment. Two non-serious adverse events of mild severity (increased ALT level and headache) were considered possibly related to rurioctocog alfa pegol. There were no deaths or treatment-related serious adverse events. No patients developed inhibitory antibodies to FVIII or persistent IgG- or IgM-binding antibodies to FVIII, PEG-FVIII or PEG., Conclusion: Rurioctocog alfa pegol was well tolerated and effective for perioperative use in patients with haemophilia A and showed no signs of immunogenicity., (© 2019 The Authors Haemophilia Published by John Wiley & Sons Ltd.)

Background: The efficacy and safety of extended half-life, full-length, pegylated recombinant factor VIII rurioctocog alfa pegol [BAX 855, ADYNOVATE (USA)/ADYNOVI (Europe); Baxalta US Inc., a Takeda company, Lexington, MA, USA] was investigated in previously treated Korean patients with severe hemophilia A (HA)., Methods: A post hoc data analysis from the international, multicenter, phase 2/3 PROLONG-ATE study of rurioctocog alfa pegol in patients with severe HA (NCT01736475) determined annualized bleeding rates (ABRs) and rates of adverse events (AEs) in Korean patients treated in this study., Results: All 10 enrolled Korean patients receiving rurioctocog alfa pegol (9 prophylaxis, 1 on-demand) completed the study [median (range) age, 28.0 (12-50) yr; weight, 64.8 (45-90) kg; 8 patients had ≥1 target joint at screening]. Median (range) ABR was 1.9 (0.0-14.5) for patients on prophylaxis and 62.2 for the patient receiving on-demand treatment. The hemostatic efficacy of rurioctocog alfa pegol was rated "excellent" or "good" and only single infusions were required per bleeding episode. ABRs improved in most patients compared with prestudy values. No dose adjustments were required for prophylaxis, and the dosing frequency was reduced in 8 patients, compared with their previous prophylaxis regimen. No serious AEs were reported; all 9 nonserious AEs (in 3 patients) were mild in severity and unrelated to the study treatment., Conclusion: This post hoc analysis of a small group of Korean patients with severe HA indicated that rurioctocog alfa pegol was effective, and no serious AEs were observed. For most patients, the dosing frequency was also reduced compared with their previous regimen., Competing Interests: Authors' Disclosures of Potential Conflicts of Interest: CWY, HJB, SKP, YSP, and H-JS have no conflicts of interest to declare. WE is an employee of Baxalta Innovations GmbH, a member of the Takeda group of companies. ST is an employee of Baxalta US Inc., a member of the Takeda group of companies, and a Takeda stock owner., (© 2019 Korean Society of Hematology.)

Introduction: FEIBA(®) consists of zymogens and traces of activated forms of procoagulant factors II, VII, IX, X, anticoagulants protein C and TFPI, and small amounts of cofactors FV, FVIII and protein S, in a balanced ratio. As shown previously, FII-FXa complex plays a key role in FEIBA's mode of action (MoA)., Methods: Thrombin generation (TG) was measured by spiking coagulation factors, cofactors and inhibitors to high titer FVIII inhibitor plasma, and in plasma samples from patients in a phase 3 clinical study evaluating the safety and efficacy of FEIBA prophylaxis in haemophilia A patients with inhibitors., Results: Increasing the FXa/FII ratio improved TG, while adding coagulation enzyme components had a negligible effect. Adding FX, FIX, and FVII increased the peak thrombin and decreased the lag time. The presence of FV and phospholipids led to faster TG, while protein C and protein S reduced the amount of peak thrombin. TFPI appeared to have no effect. Patients on prophylaxis with FEIBA(®) showed higher peak thrombin and AUC with elevated FII, FX, FIX, FVIIa, and protein C levels, and experienced significantly less bleeding episodes than those receiving on-demand treatment., Conclusion: These experiments showed that although the FII-FXa complex induced immediate thrombin formation on the activated platelet surface, other procoagulant components of FEIBA were necessary to achieve an optimal thrombin burst. The presence of the pro- and anti-coagulants in FEIBA provides a haemostatic balance, and is thus expected to prevent thrombotic events. Recent clinical data verified the postulated MoA of FEIBA in prophylaxis treatment., (© 2016 The Authors. Haemophilia Published by John Wiley & Sons Ltd.)

High titers of serum IgG2 reactive with Actinobacillus actinomycetemcomitans are present in early-onset periodontitis (EOP) patients and it appears that anti-A. actinomycetemcomitans may be protective. Smoking is associated with increased periodontal disease severity in generalized early-onset periodontitis (G-EOP) patients, but is not associated with periodontal disease severity in patients with localized juvenile periodontitis (LJP). Furthermore, smoking is associated with reduced serum IgG2 levels in black patients with G-EOP but not in those with LJP. Based on this selective effect of smoking, we hypothesized that smoking would be associated with a reduction of specific IgG2 reactive with A. actinomycetemcomitans in black G-EOP patients but not black LJP patients. In addition, we examined IgG2 responses to carbohydrate antigens from non-periodontal pathogens including Haemophilus influenzae b oligosaccharide antigen (Hib) and the Streptococcus pneumoniae antigen phosphocholine (PC). Smoking status was assessed from serum cotinine levels, and IgG2 specific for A. actinomycetemcomitans, Hib, and PC was assessed by ELISA. Our study revealed that smoking was correlated with a dramatic reduction in serum IgG2 anti-A. actinomycetemcomitans in G-EOP smokers but not in LJP smokers. In contrast, anti-Hib IgG2 and anti-PC IgG2 were not affected in either G-EOP or LJP patients. In short, these results indicate that smoking is associated with a reduction in serum IgG2 anti-A. actinomycetemcomitans in black G-EOP subjects, but IgG2 reactive with other antigens may not be reduced in G-EOP smokers.

This review summarizes the current data on the effects of smoking and tobacco on the immune system and its potential impact on periodontal health. Smokers are 2.5-6 times more likely to develop periodontal disease than non-smokers, and there is evidence for a direct correlation between the number of cigarettes smoked and the risk of developing disease. Tobacco users also tend to exhibit increased severity of periodontal disease. Direct correlations between tobacco use and increased attachment loss and pocket depth and reduced bone crest height have been reported. Although the correlation between tobacco use and periodontal disease is quite strong, the role of tobacco in the pathogenesis of periodontal disease is uncertain. Recent studies indicate that one potential mechanism is that tobacco use exacerbates periodontal disease because it alters the immune response to periodontal pathogens. Indeed, smokers exhibit increased numbers of peripheral blood mononuclear phagocytes which appear to be functionally compromised. Inadequate phagocyte activity could reduce the clearance of pathogens from the oral cavity and thereby facilitate the development of periodontal disease. Tobacco-exposed B- and T-lymphocytes exhibit reduced proliferative capacities which could limit the production of protective immunoglobulins against oral pathogens. The risk factors for periodontal disease can be broadly classified as genetic, environmental, host-response factors, and host-related factors such as age. Tobacco, an environmental factor, undermines the host response and may facilitate the development and progression of periodontal disease. This review highlights the inter-relatedness of two of the risk factors associated with periodontal disease.

Susceptibility to early-onset periodontitis (EOP) appears to be attributable to a gene inherited in an autosomal dominant pattern. This explains why EOP clusters in families and why about half of the family members develop periodontal disease early in life. Manifestation of EOP is variable, with some patients having a localized form restricted to first molars and incisors (LJP) and others with a severe generalized form of periodontitis (SP). The extent and severity of disease is less in patients who are seropositive for Actinobacillus actinomycetemcomitans than in seronegative patients, and this relationship prompted the hypothesis that anti-A. actinomycetemcomitans helps limit disease. The dominant antibody is an IgG2 reactive with the serotypespecific carbohydrate. The incidence of the LJP form of EOP is about 10 times higher in blacks than in whites. Interestingly, blacks have higher levels of serum IgG2, a higher frequency of anti-A. actinomycetemcomitans antibody, and higher serum titers of IgG2 anti-A. actinomycetemcomitans which may help explain why the disease is localized. Studies in progress suggest that smoking reduces serum IgG2 levels in SP patients and is associated with more severe periodontal destruction. In marked contrast, IgG2 does not appear to be reduced in LJP patients who smoke, and smoking does not appear to increase periodontal destruction. We think that IgG2 anti-A. actinomycetemcomitans is playing a role in limiting the extent and severity of disease in patients genetically susceptible to EOP. J Periodontol 1996;67:317-322., (© 1996 American Academy of Periodontology.)

Aminopeptidase N (EC 3.4.11.2) (APN) is an ectopeptidase expressed in lung at the apical surface of alveolar type II epithelial cells. Its expression is up-regulated during fetal lung development. Recently several ectopeptidases have been recognized as possible regulators of growth and cell differentiation through their role in hydrolysis of autocrine and paracrine peptides that influence these processes. The studies reported here describe effects of factors known to promote lung development and differentiation of the alveolar epithelium on expression of aminopeptidase N during fetal lung development in organ culture. Fetal rat lung was placed in organ culture at the 15th gestational day and cultured for 6 days in the presence or absence of the synthetic glucocorticoid hormone dexamethasone or epidermal growth factor (EGF). Steady-state levels of APN mRNA increased approximately 10-fold during the 6-day culture. During this time the lung alveolar epithelium developed to the point where immature alveolar type II cells were recognized by the presence of lamellar bodies. Dexamethasone or EGF increased the levels of APN mRNA in the fetal lung 2-to 3-fold over control cultures by the third day in culture and concurrently accelerated the morphological development of the alveolar epithelium. Differences in treated and control cultures diminished after 6 days in culture when the epithelium appeared more mature, suggesting that the immature epithelium was more responsive to the treatments.